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Prof. Jadhav M. V., Er. Shaikh A. P., Er. Gite B.E., Er. Yadav A. P. / International Journal of
Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 2, Issue 6, November- December 2012, pp.1690-1694
Sand Dam Reservoir – Need Of Semi Arid Areas
Prof. Jadhav M. V.1, Er. Shaikh A. P.2, Er. Gite B.E.3, Er. Yadav A. P.4
1,Department of Civil Engineering, Sanjivini College of Engineering, Kopergaon,
Maharashtra, India.
2, 3,4. Department of Civil Engineering, Amrutvahini College of Engineering,
Sangamner, Maharashtra, India.

ABSTRACT:
In dry land areas of India, episodic impermeable layer. It is constructed across a river to
shortages of water are quite common. In many block the subsurface flow of water, hence creating a
areas, Women have to spend days traveling long reservoir upstream of the dam within the riverbed
distances looking for water. Any development or material. The main function of sand dams is to store
rehabilitation of water supply schemes should water in the sand of the riverbed and therefore
aim to ensure reliable and adequate water supply increase the volume of sand and water in riverbeds.
and sanitation. The development of appropriate The reservoir will be filled due to percolation of
and affordable community water supply systems water during flood events. The water within the
calls for innovative rain and runoff water riverbed (reservoir) can be used for domestic use
management technologies for domestic, livestock, and livestock. Other functions of sand dams can be
and supplemental irrigation uses. The water held sand harvesting, rehabilitation of gullies and
in sand dam behind the dam spread horizontally groundwater recharge.
creating a permanent increase in water table A sand dam has several functions:
allowing trees grow natural and transforming the  Increasing water supply by storing water in
local ecology. The dam creates a natural buffer the sandy riverbed
that reduces the threat posed by flooding and  Sand harvesting and rehabilitating of
drought & built resilience of communities to cope gullies
with the impacts of climate change in semiarid  Groundwater recharge
regions. Sand dam retains 25 % water of sand
stored on its upstream which will flow down if 1.1 Objective
the sand dam is not constructed. Sand dams are  To increase the water table higher and over a
relatively simple to construct and can be built by larger area compared to individual units.
a constituent community for their own  To provide ecological regeneration.
empowerment and self-sufficiency. The materials  To provide drinking water and also water for
required are mostly local and reconfigured from rural commercial development activities.
the stream itself.  To protect water against evaporation.
 Block the underground flow of water between
Keywords - Ground water, permeability, sand the voids in the sand.
dam, sand reservoir.
1.2 Need Of Sand Dam
1. INTRODUCTION The semi-arid region in which rural
A sand storage dam or sand dam is a small communities depend mostly on livestock farming
dam build on and into the riverbed of a seasonal and small-scale agriculture, both activities are
river. The functioning of a sand dam is based on highly constrained by water availability, there being
sedimentation of coarse sand upstream of the no perennial rivers and with rainfall varying highly,
structure by which the natural storage capacity of both spatially and temporally. Water harvesting has
the riverbed aquifer is enlarged. The aquifer fills proven to be an attractive decentralized water source
with water during the wet season, resulting from in areas where other means of water supply have
surface runoff and groundwater recharge within the little potential. However, roof water harvesting is
catchments. When the riverbed aquifer is full, not effective from thatched roofs and storage of
usually within one or two large rainfall events, the surface runoff in tanks can only provide sufficient
river starts to flow as it does in the absence of the water for the dry period and the quality is
dam. However, the groundwater flow through the questionable. Therefore the sand dam technology
riverbed is now obstructed by the sand storage dam, provides an attractive solution for the people.
creating additional groundwater storage for the
community.
A sand dam is a partially subsurface dam
build in a dry and sandy riverbed onto bedrock or an

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based on precipitation compared to regions with a
lower annual rainfall. Also, to calculate the yield of
a sand dam, it is essential to know the
climatologically behavior of an area.
Rainfall data of last 30 years was collected and
shown in Table no.1
Average rainfall = 12143.6/ 30
= 404.78 mm

2.4 Measurement of Sand Depth
The depth of the basement or impermeable
layer in the riverbed with respect to the riverbed
Fig. No. 1: Pravara River at Sangamner surface is of importance to decide where the sand
storage dam should be build. It should be
2. METHODOLOGY constructed at the location where the impermeable
2.1 Basic Principle: layer is closest to the riverbed surface. Preferably,
the basement upstream of this location is deeper, to
get a larger sand dam aquifer. The depth of the sand
in the riverbed can be surveyed by using an iron rod
with a diameter of 16 mm (5/8”) notches should be
cut in the probing rods for every 25 cm to collect
sand samples when the rods are pulled up.
Other method for measurement of sand
depth is core drilling. This method is used because
the depth of sand in river is more than the length of
probing rod. So we used core drilling method, in this
method hollow hard iron pipe with beveled mouth
edge cutter is inserting in the sand bed, Sand depth
is measured with this method at a site is = 9.0 m.
Fig No. 2: Important Water Balance Components

Water balance components-
ET- Evapo (transpi) ration from slopes.
E - Evaporation from riverbed.
P - Precipitation.
R -Surface runoff from slopes to river.
Bs - Groundwater base flow from slopes to river.
Bf - Shallow and deep longitudinal base flow.
Qout-River discharge outflow over downstream dam.
Lout- Leakage underneath and around downstream Fig. No.3: Core Drilling
dam.
Qin - River discharge inflow over upstream dam. 2.5 Longitudinal Profile and Cross Section
Up - Use of water (abstraction). The potential riverbed section(s) should be
Gr-Loss of water into the ‘impermeable ground. investigated in further detail for suitability for Sand
dams. This can be done by taking measurements of
2.2 Practical steps within a Sand Dam the riverbed dimensions along the selected river
Project section. Here 250m of longitudinal level profile is
The step-wise approach in how to carry out. & 10m interval for cross section profile.
implement a sand dam project is shown in fig. No.
7. By referring fig. No. 7 for the purpose of sand
dam construction, select the site at Sangamner
locality in the basin of Pravara river from the study
of site condition, nature of river bed and the strata of
river bed. After selecting proper site and location the
field work is done. In field work the longitudinal
and cross section profile levelling is done.

2.3 Precipitation and Evaporation Data:
Higher annual precipitation will mean more
storm events. These areas have a higher suitability

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Fig. No. 5 Cross Section at 100m Chainage

By knowing the longitudinal and cross-
sectional profile, a calculation of the reservoir
capacity can be made. In figure 5 is given of a cross-
section where the sand is deepest. It is important to
take measurements every 10 meter across the
riverbed to determine the riverbed morphology.

2.6 Determination of Permeability
As per IS 2720, The coefficient of
Fig. No.4: Longitudinal Profile permeability of sand is found out by constant head
permeability method on compacted sample of sand
by constant head permeameter.
The coefficient of permeability of sand is 0.
1342× 𝟏𝟎−𝟐 mm/sec. The type of sand is medium
sand which has Good Drainage property As per IS
2720.

3. HYDROLOGICAL DESIGN
Maximum discharge formula=
1 2 1
 A  R 3  S2
n
Where, n = 0.025 for good river condition.
1
S= from L-section.
425
P = Perimeter 125m measured at site.
Normal flood level = 5.27m.
Cross section of river for design shown in fig no.6
100 +120
A= ( ) 5.27=579.7𝑚2
2

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𝐴 579.4 that reduces the threat posed by flooding and
R= 𝑃
= 125
= 4.64m
drought & built resilience of communities to cope
1 with the impacts of climate change in semiarid
1 2 1 2 regions. Sand dam retains 25 % water of sand stored
Q= × 579.7 × (4.64)3 ×( ) on its upstream which will flow down if the sand
0.025 dam is not constructed.
425
= 3146.78𝑚2 Sand dams are relatively simple to
Discharge through sand construct and can be built by a constituent
Q= KiA community for their own empowerment and self-
sufficiency. The materials required are mostly local
= 0.1342 × 10−2 × 10−3 × 12.18 ×
100 +50 and reconfigured from the stream itself. Should
( 2 )×9 the infrastructure fail, it can be repaired or remade.
= 0.01 Cumec --- Very small hence Insects that carry water-borne diseases are absent as
neglected they cannot breed in dry sand topping the
Sand storage capacity of dam underground water reservoir. For the same reason,
L×T×D
Volume of Sand (V sand) = no pollution is caused by frogs, snakes and other
6
100 ×9×500 animals as they cannot live in the sand. Pollution
= 6
= 75× 103 Cu.m from livestock and other animals is nearly absent as
L =Length of Dam Wall water is under the surface of the upper dry sand.
T =Max through Back assume-500m
D =Depth of Sand REFERENCES
25 1. R. Lasage a, j. Aerts a, g.-c.m. mutiso b, a.
Vol. of water extraction = 75× 103 × De vries c, “Potential for community based
100 adaptation to droughts: Sand dams in kitui,
= 18750 Cu. m
kenya” 18 may 2007.
= 18.75× 106 liters
2. Aerts, J.C.J.H., 2005. Adaptation for river
4. CONCLUSIONS basins: connecting policy goals to the
Water scarcity is perceived as the major water resources system. Water Science and
bottleneck to development in the arid and semi-arid Technology 51 (5), 121–131.
and innovative ways of rainwater harvesting are 3. Beimers, P.B., van Eick, A.J., Lam, K.S.,
worthwhile. Sand dam technology that artificially Roos, B., 2001. Building sand-storage
enhances traditional water harvesting knowledge if dams, SASOL Foundation Kitui District,
well sited can bank of up to sufficient capacity of Kenya, Practical work report, Delft
clean water for domestic use thereby alleviating University of Technology, p. 100.
water shortages during drought periods. Drinking 4. Borst, L., de Haas, S.A., 2006. Hydrology
water or potable water is water pure enough to be of sand storage dams: a case study in the
consumed or used with low risk of immediate harm. Kiindu catchment, Kitui District, Kenya,
The water supplied by sand dam is used for Vrije Univer-siteit, Amsterdam, p. 146.
households, commercial and industry is all of 5. Central Bureau of Statistics, 2001. 1999
drinking water standard, even though only a small Population and Housing Census, vol. II,
proportion is actually consumed or used in food Govenment printer, Nairobi
preparation. Typical uses include washing or 6. Nissen-Petersen, E., 1982. Rain catchments
landscape irrigation. and water supply in rural Africa: a manual.
The water held in sand dam behind the dam spread United Kingdom, Hodder and Stoughton.
horizontally creating a permanent increase in water Bungay, Suffolk, UK, p. 83.
table allowing trees grow natural and transforming
the local ecology. The dam creates a natural buffer

Table No. 1: Annual rainfall data of Sangamner city
Year 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990
Rainfall 459 315 363 204 204 260 306 461 458 445
(mm)
Year 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000
Rainfall 450 342 435 416.6 290 566 402 489 348 528
(mm)
Year 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Rainfall 337 459 380 570 456 485 391 469 403 352
(mm)

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Fig. No.6 : Cross section of river
1. Possibility map for Sand dams (Catchment Level)
2. Field work: Collecting field data & Verifying Possibility
Site Selection map (Catchment Level)
3. Fieldwork : Taking measurements at potential river beds
for sand dams
4. Selecting location for sand dam

1. Getting base line data from local community to determine water
Water Demand and
demand
Water Yield
2. Making rough estimation on water storage of sand dam
3. Determining social economic & environmental impact of sand
dam

Design 1. Calculating maximum discharge in river bed

Excavation, Construction
and Maintenance

Fig. No.7 Practical Steps for Sand Dam

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